/*
* Get an nfsv4 vnode of the given fid from the visible list of an
* nfs filesystem or get the exi_vp if it is the root node.
*/
int
nfs4_vget_pseudo(struct exportinfo *exi, vnode_t **vpp, fid_t *fidp)
{
fid_t exp_fid;
struct exp_visible *visp;
int error;
/* check if the given fid is in the visible list */
for (visp = exi->exi_visible; visp; visp = visp->vis_next) {
if (EQFID(fidp, &visp->vis_fid)) {
VN_HOLD(visp->vis_vp);
*vpp = visp->vis_vp;
return (0);
}
}
/* check if the given fid is the same as the exported node */
bzero(&exp_fid, sizeof (exp_fid));
exp_fid.fid_len = MAXFIDSZ;
error = vop_fid_pseudo(exi->exi_vp, &exp_fid);
if (error)
return (error);
if (EQFID(fidp, &exp_fid)) {
VN_HOLD(exi->exi_vp);
*vpp = exi->exi_vp;
return (0);
}
return (ENOENT);
}
/*
* Get the change attribute from visible and returns TRUE.
* If the change value is not available returns FALSE.
*/
bool_t
nfs_visible_change(struct exportinfo *exi, vnode_t *vp, timespec_t *change)
{
struct exp_visible *visp;
fid_t fid;
treenode_t *node;
/*
* First check to see if vp is export root.
*/
if (VN_CMP(vp, exi->exi_vp))
goto exproot;
/*
* Only a PSEUDO node has a visible list or an exported VROOT
* node may have a visible list.
*/
if (!PSEUDO(exi))
exi = get_root_export(exi);
/* Get the fid of the vnode */
bzero(&fid, sizeof (fid));
fid.fid_len = MAXFIDSZ;
if (vop_fid_pseudo(vp, &fid) != 0)
return (FALSE);
/*
* We can't trust VN_CMP() above because of LOFS.
* Even though VOP_CMP will do the right thing for LOFS
* objects, VN_CMP will short circuit out early when the
* vnode ops ptrs are different. Just in case we're dealing
* with LOFS, compare exi_fid/fsid here.
*/
if (EQFID(&exi->exi_fid, &fid) &&
EQFSID(&exi->exi_fsid, &vp->v_vfsp->vfs_fsid))
goto exproot;
/* See if it matches any fid in the visible list */
for (visp = exi->exi_visible; visp; visp = visp->vis_next) {
if (EQFID(&fid, &visp->vis_fid)) {
*change = visp->vis_change;
return (TRUE);
}
}
return (FALSE);
exproot:
/* The VROOT export have its visible available through treenode */
node = exi->exi_tree;
if (node != ns_root) {
ASSERT(node->tree_vis != NULL);
*change = node->tree_vis->vis_change;
} else {
ASSERT(node->tree_vis == NULL);
*change = ns_root_change;
}
return (TRUE);
}
/*
* Returns true if the supplied vnode is the
* directory of an export point.
*/
int
nfs_exported(struct exportinfo *exi, vnode_t *vp)
{
struct exp_visible *visp;
fid_t fid;
/*
* First check to see if vp is the export root
* This check required for the case of lookup ..
* where .. is a V_ROOT vnode and a pseudo exportroot.
* Pseudo export root objects do not have an entry
* in the visible list even though every V_ROOT
* pseudonode is visible. It is safe to compare
* vp here because pseudo_exportfs put a hold on
* it when exi_vp was initialized.
*
* Note: VN_CMP() won't match for LOFS shares, but they're
* handled below w/EQFID/EQFSID.
*/
if (VN_CMP(vp, exi->exi_vp))
return (1);
/* Get the fid of the vnode */
bzero(&fid, sizeof (fid));
fid.fid_len = MAXFIDSZ;
if (vop_fid_pseudo(vp, &fid) != 0)
return (0);
if (EQFID(&fid, &exi->exi_fid) &&
EQFSID(&vp->v_vfsp->vfs_fsid, &exi->exi_fsid)) {
return (1);
}
/* See if it matches any fid in the visible list */
for (visp = exi->exi_visible; visp; visp = visp->vis_next) {
if (EQFID(&fid, &visp->vis_fid))
return (visp->vis_exported);
}
return (0);
}
/*
* Return true if the supplied vnode has a sub-directory exported.
*/
int
has_visible(struct exportinfo *exi, vnode_t *vp)
{
struct exp_visible *visp;
fid_t fid;
bool_t vp_is_exported;
vp_is_exported = VN_CMP(vp, exi->exi_vp);
/*
* An exported root vnode has a sub-dir shared if it has a visible list.
* i.e. if it does not have a visible list, then there is no node in
* this filesystem leads to any other shared node.
*/
if (vp_is_exported && (vp->v_flag & VROOT))
return (exi->exi_visible ? 1 : 0);
/*
* Only the exportinfo of a fs root node may have a visible list.
* Either it is a pseudo root node, or a real exported root node.
*/
exi = get_root_export(exi);
if (!exi->exi_visible)
return (0);
/* Get the fid of the vnode */
bzero(&fid, sizeof (fid));
fid.fid_len = MAXFIDSZ;
if (vop_fid_pseudo(vp, &fid) != 0) {
return (0);
}
/*
* See if vp is in the visible list of the root node exportinfo.
*/
for (visp = exi->exi_visible; visp; visp = visp->vis_next) {
if (EQFID(&fid, &visp->vis_fid)) {
/*
* If vp is an exported non-root node with only 1 path
* count (for itself), it indicates no sub-dir shared
* using this vp as a path.
*/
if (vp_is_exported && visp->vis_count < 2)
break;
return (1);
}
}
return (0);
}
/*
* Returns true if the supplied vnode is visible
* in this export. If vnode is visible, return
* vis_exported in expseudo.
*/
int
nfs_visible(struct exportinfo *exi, vnode_t *vp, int *expseudo)
{
struct exp_visible *visp;
fid_t fid;
/*
* First check to see if vp is export root.
*
* A pseudo export root can never be exported
* (it would be a real export then); however,
* it is always visible. If a pseudo root object
* was exported by server admin, then the entire
* pseudo exportinfo (and all visible entries) would
* be destroyed. A pseudo exportinfo only exists
* to provide access to real (descendant) export(s).
*
* Previously, rootdir was special cased here; however,
* the export root special case handles the rootdir
* case also.
*/
if (VN_CMP(vp, exi->exi_vp)) {
*expseudo = 0;
return (1);
}
/*
* Only a PSEUDO node has a visible list or an exported VROOT
* node may have a visible list.
*/
if (! PSEUDO(exi))
exi = get_root_export(exi);
/* Get the fid of the vnode */
bzero(&fid, sizeof (fid));
fid.fid_len = MAXFIDSZ;
if (vop_fid_pseudo(vp, &fid) != 0) {
*expseudo = 0;
return (0);
}
/*
* We can't trust VN_CMP() above because of LOFS.
* Even though VOP_CMP will do the right thing for LOFS
* objects, VN_CMP will short circuit out early when the
* vnode ops ptrs are different. Just in case we're dealing
* with LOFS, compare exi_fid/fsid here.
*
* expseudo is not set because this is not an export
*/
if (EQFID(&exi->exi_fid, &fid) &&
EQFSID(&exi->exi_fsid, &vp->v_vfsp->vfs_fsid)) {
*expseudo = 0;
return (1);
}
/* See if it matches any fid in the visible list */
for (visp = exi->exi_visible; visp; visp = visp->vis_next) {
if (EQFID(&fid, &visp->vis_fid)) {
*expseudo = visp->vis_exported;
return (1);
}
}
*expseudo = 0;
return (0);
}
/*
* When we export a new directory we need to add a new
* path segment through the pseudofs to reach the new
* directory. This new path is reflected in a list of
* directories added to the "visible" list.
*
* Here there are two lists of visible fids: one hanging off the
* pseudo exportinfo, and the one we want to add. It's possible
* that the two lists share a common path segment
* and have some common directories. We need to combine
* the lists so there's no duplicate entries. Where a common
* path component is found, the vis_count field is bumped.
*
* This example shows that the treenode chain (tree_head) and
* exp_visible chain (vis_head) can differ in length. The latter
* can be shorter. The outer loop must loop over the vis_head chain.
*
* share /x/a
* mount -F ufs /dev/dsk/... /x/y
* mkdir -p /x/y/a/b
* share /x/y/a/b
*
* When more_visible() is called during the second share,
* the existing namespace is following:
* exp_visible_t
* treenode_t exportinfo_t v0 v1
* ns_root+---+ +------------+ +---+ +---+
* t0| / |........| E0 pseudo |->| x |->| a |
* +---+ +------------+ +---+ +---+
* | / /
* +---+ / /
* t1| x |------------------------ /
* +---+ /
* | /
* +---+ /
* t2| a |-------------------------
* +---+........+------------+
* | E1 real |
* +------------+
*
* This is being added:
*
* tree_head vis_head
* +---+ +---+
* t3| x |->| x |v2
* +---+ +---+
* | |
* +---+ +---+ v4 v5
* t4| y |->| y |v3 +------------+ +---+ +---+
* +---+\ +---+ | E2 pseudo |->| a |->| b |
* | \....... >+------------+ +---+ +---+
* +---+ / /
* t5| a |--------------------------- /
* +---+ /
* | /
* +---+-------------------------------
* t6| b | +------------+
* +---+..........>| E3 real |
* +------------+
*
* more_visible() will:
* - kmem_free() t3 and v2
* - add t4, t5, t6 as a child of t1 (t4 will become sibling of t2)
* - add v3 to the end of E0->exi_visible
*
* Note that v4 and v5 were already processed in pseudo_exportfs() and
* added to E2. The outer loop of more_visible() will loop only over v2
* and v3. The inner loop of more_visible() always loops over v0 and v1.
*
* Illustration for this scenario:
*
* mkdir -p /v/a/b/c
* share /v/a/b/c
* mkdir /v/a/b/c1
* mkdir -p /v/a1
* mv /v/a/b /v/a1
* share /v/a1/b/c1
*
* EXISTING
* treenode
* namespace: +-----------+ visibles
* |exportinfo |-->v->a->b->c
* connect_point->+---+--->+-----------+
* | / |T0
* +---+
* | NEW treenode chain:
* child->+---+
* | v |T1 +---+<-curr
* +---+ N1| v |
* | +---+
* +---+ |
* | a |T2 +---+<-tree_head
* +---+ N2| a1|
* | +---+
* +---+ |
* | b |T3 +---+
* +---+ N3| b |
* | +---+
* +---+ |
* | c |T4 +---+
* +---+ N4| c1|
* +---+
*
* The picture above illustrates the position of following pointers after line
* 'child = tree_find_child_by_vis(connect_point, curr->tree_vis);'
* was executed for the first time in the outer 'for' loop:
*
* connect_point..parent treenode in the EXISTING namespace to which the 'curr'
* should be connected. If 'connect_point' already has a child
* with the same value of tree_vis as the curr->tree_vis is,
* the 'curr' will not be added, but kmem_free()d.
* child..........the result of tree_find_child_by_vis()
* curr...........currently processed treenode from the NEW treenode chain
* tree_head......current head of the NEW treenode chain, in this case it was
* already moved down to its child - preparation for another loop
*
* What will happen to NEW treenodes N1, N2, N3, N4 in more_visible() later:
*
* N1: is merged - i.e. N1 is kmem_free()d. T0 has a child T1 with the same
* tree_vis as N1
* N2: is added as a new child of T1
* Note: not just N2, but the whole chain N2->N3->N4 is added
* N3: not processed separately (it was added together with N2)
* Even that N3 and T3 have same tree_vis, they are NOT merged, but will
* become duplicates.
* N4: not processed separately
*/
static void
more_visible(struct exportinfo *exi, treenode_t *tree_head)
{
struct exp_visible *vp1, *vp2, *vis_head, *tail, *next;
int found;
treenode_t *child, *curr, *connect_point;
vis_head = tree_head->tree_vis;
connect_point = exi->exi_tree;
/*
* If exportinfo doesn't already have a visible
* list just assign the entire supplied list.
*/
if (exi->exi_visible == NULL) {
tree_add_child(exi->exi_tree, tree_head);
exi->exi_visible = vis_head;
return;
}
/* The outer loop traverses the supplied list. */
for (vp1 = vis_head; vp1; vp1 = next) {
found = 0;
next = vp1->vis_next;
/* The inner loop searches the exportinfo visible list. */
for (vp2 = exi->exi_visible; vp2; vp2 = vp2->vis_next) {
tail = vp2;
if (EQFID(&vp1->vis_fid, &vp2->vis_fid)) {
found = 1;
vp2->vis_count++;
VN_RELE(vp1->vis_vp);
/* Transfer vis_exported from vp1 to vp2. */
if (vp1->vis_exported && !vp2->vis_exported)
vp2->vis_exported = 1;
kmem_free(vp1, sizeof (*vp1));
tree_head->tree_vis = vp2;
break;
}
}
/* If not found - add to the end of the list */
if (! found) {
tail->vis_next = vp1;
vp1->vis_next = NULL;
}
curr = tree_head;
tree_head = tree_head->tree_child_first;
if (! connect_point) /* No longer merging */
continue;
/*
* The inner loop could set curr->tree_vis to the EXISTING
* exp_visible vp2, so we can search among the children of
* connect_point for the curr->tree_vis. No need for EQFID.
*/
child = tree_find_child_by_vis(connect_point, curr->tree_vis);
/*
* Merging cannot be done if a valid child->tree_exi would
* be overwritten by a new curr->tree_exi.
*/
if (child &&
(child->tree_exi == NULL || curr->tree_exi == NULL)) {
if (curr->tree_exi) { /* Transfer the exportinfo */
child->tree_exi = curr->tree_exi;
child->tree_exi->exi_tree = child;
}
kmem_free(curr, sizeof (treenode_t));
connect_point = child;
} else { /* Branching */
tree_add_child(connect_point, curr);
connect_point = NULL;
}
}
}
